MUTAGENIC ACTIVITY OF GLYCINE UPON NITROSATION IN THE PRESENCE OF CHLORIDE AND HUMAN GASTRIC-JUICE - A POSSIBLE ROLE IN GASTRIC CARCINOGENESIS

The mutagenic activity of glycine upon nitrosation was studied in the Ames tester strains TA98, TA100, TA102, and TA104. The results obtaine d show that glycine at acidic pH values and in the presence of Cl- can react with nitrite giving rise to genotoxic compounds to the tester s trains used. When these experiments were carried out in the presence o f gastric juice the genotoxicity observed was associated with the Cl- concentration in the different gastric juice samples. The nature and t he mechanism of genetic lesion induced by the ultimate genotoxicant ar ising from the nitrosation of glycine are not fully understood. Primar y amines (e.g., amino acids) have been described as potential alkylati ng agents after nitrosation. However, in our experimental conditions t hese alkylating activities were not detected, suggesting that other me chanisms could be involved in the genetic lesion induced by nitrosated glycine. The influence of Cl- in the genotoxic activity of glycine an d other primary amines upon nitrosation and its possible involvement i n the etiology of gastric cancer are discussed. (C) 1997 Wiley-Liss, I nc.